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Notes: The microstructure of Al2O3 formed by oxidation of a model NiCrAlY alloy during electron-beam physical vapor deposition of ZrO2–7.6 mol% YO1.5 is examined and compared with that formed on the bare substrate. The growth rate, morphology, and chemical composition of the oxide vary among the different constituents of the alloy surface and are further influenced by the O2 partial pressure and the physical presence of the thermal barrier coating (TBC) layer. These differences, however, are largely limited to the outer oxide layer. The interplay between the TBC and the growing oxide leads to the formation of a fine-grain Al2O3–ZrO2“mixed zone” within the thermally grown oxide. A mechanism is outlined to explain this behavior, based on the dissolution of ZrO2 in a transient Al2O3 structure growing by outward diffusion of Al, and its subsequent reprecipitation when the metastable phase transforms to the stable α-Al2O3 form.

Notes: This article reports the results of a study conducted to examine the ability of the Situational Outlook Questionnaire (SOQTM) to effectively discern climates that either encourage or discourage creativity and the ability to initiate change in a team setting. The purpose of the study is to examine the concurrent criterion–related validity of the SOQ. The article explores the characteristics in an organisational climate that promote teamwork and some of the tripwires one needs to be aware of in the formation and management of teams. Nine dimensions of the climate for creativity and change as measured by the Situational Outlook Questionnaire are put forward and defined in relation to teams. The methodology and results of the study are reported. The results show that when subjects (N7equals;154) complete the SOQ based on their recollection of a best– and worst–case team experience, the measure is able to consistently and significantly discriminate between the two types of experiences. Conclusions, implications, and areas for future research to further examine the validity of the SOQ are explored.

Notes: The compatibility of dense nonaqueous phase liquids (DNAPLs). triehloroelhylene (TCE), methylene chloride (MC), and creosote with commercially available sodium bentonite pellets was evaluated using stainless steel, double ring, falling head permeameters. The hydraulic conductivity (K) of the bentonite clay was measured under three experimental conditions: (1) water soluble constituents of the DNAPLs were used to hydrate and permeate the bentonite: (2) bentonite pellets were submersed in DNAPL prior to hydration and permeation with water: and (3) DNAPLs were pooled on water-hydrated bentonite. Further, the effect of hydraulic head (2.5. 145, and 710 cm) on water-hydrated bentonite permeated with TCE and the effects of TCE exposure time to mixtures of bentonite grout and sand were measured. Solubility concentrations of DNAPL constituents did not effect the hydraulic conductivity of the bentonite pellets relative to baseline (water only) measurements; a competent hydraulic barrier was formed (K 〈 5 × 10−9 cm/s). Bentonite pellets submersed in DNAPLs retained their rigid shape, did not swell, and did not perform as a hydraulic barrier. However, when the DNAPL was removed and replaced with water, the DNAPL-wetted pellets imbibed water to swell and form an adequate hydraulic barrier (K 〈 6 × 10−9 cm/s). Competent hydraulic barriers constructed with bentonite pellets and hydrated with water were subsequently permeated with TCE, MC, or creosote DNAPLs developing desiccation cracks up to 5 mm wide. The intrinsic permeability of water-hydrated bentonite was 46 to 2640 limes greater to DNAPLs relative to water, indicating that the desiccation cracks predominantly facilitated preferential DNAPL transport. The propagation rate of cracks was positively correlated to the hydraulic gradient, bin the formation of cracks is chemically dependent on the contact lime of DNAPL. Silica sand is expansively inert, yet 95, 90, 83, 75, and 50% (wt sand/wt bentonite) mixtures with bentonite grout were insufficient to prevent desiccation cracks and hydraulic failure. The incompatibility between DNAPLs and bentonite observed in this study is important due id the numerous exploratory borings in DNAPL/ones, the increasing dependency on hydraulic containment as a remedial alternative, and the fact that such remedial systems are often designed to be functional for many years.

Notes: : Municipalities will be implementing structural best management practices at increasing rates in their effort to comply with Phase II of the National Pollutant Discharge Elimination System (NPDES). However, there is evidence that structural best management practices (BMPs) by themselves may be insufficient to attain desired water quality standards. This paper reports on an analysis of the median removal efficiencies of structural BMPs and compares them to removal efficiencies estimated as being necessary to attain water quality standards in the Rouge River in Detroit, Michigan. Eight water quality parameters are reviewed using data collected from 1994 to 1999 in the Rouge River. Currently, five of the eight parameters in the Rouge River including bacteria, biochemical oxygen demand, and total suspended solids (TSS) exceed the required water quality standards. The reported analysis of structural BMP efficiencies reveals that structural BMPs appear capable of reducing only some of the pollutants of concern to acceptable levels.

Notes: Abstract: Ichthyosis bullosa of Siemens (IBS) is a rare disorder of cornification characterized by blister formation in the upper suprabasal layers of the epidermis. Molecular analysis of IBS has identified mutations in the keratin 2e (K2e) gene, which is located in the type II keratin gene cluster on chromosome 12q. We have studied two IBS families and have identified heterozygous point mutations in codon 493 of the K2e gene in both families. Whereas a non-conservative amino acid substitution at position 117 of the 2B region of K2e (E117K) was associated with a severe phenotype in family 1, family 2 showed mild clinical features as a result of a conservative substitution (E117D). These data suggest a phenotype–genotype correlation in these families.

Notes: Neurons of the dorsal nucleus reticularis pontis caudalis (nPontc) fire rhythmically during fictive mastication, while neurons of the ventral half tend to fire tonically (Westberg et al., 2001). This paper describes the changes in the pattern of rhythmical mastication elicited by stimulation of the sensorimotor cortex during inhibition or excitation of neurons in this nucleus and adjacent parts of nucleus reticularis gigantocellularis (Rgc) in the anaesthetized rabbit. Masticatory movements and electromyographic (EMG) activity of the masseter and digastric muscles produced by cortical stimulation were recorded before, during and after injections of a local anaesthetic (lidocaine) or excitatory amino acid N-methyl-d-aspartate (NMDA) into nPontc and Rgc through a microsyringe with attached microelectrode to record neuronal activity. Lidocaine inhibited local neurons and modified the motor program, and the effects varied with the site of injection. Most injections into the ventral half of nPontc increased cycle duration, digastric burst duration and burst area. The action of lidocaine in dorsal nPontc was more variable, although burst duration and area were often decreased. The effects on the muscle activity were always bilateral. Lidocaine block of the rostromedial part of Rgc had no effect on movements or on EMGs. Injections of NMDA excited local neurons and when injected into ventral nPontc, it completely blocked mastication. Dorsal injections either had no effect or increased cycle frequency, while decreasing burst duration and area. No increases in EMG burst duration or area were observed with NMDA. Our findings suggest that neurons of ventral nPontc tonically inhibit other parts of the central pattern generator during mastication, while dorsal neurons have mixed effects. We incorporated these findings into a new model of the masticatory central pattern generator.